Such an oil-derived hydrocarbon converter includes a hydrocarbon catalytic cracking baffle in the presence of catalyst particles in fluidized phase and which fractionated oil cuts are recovered by ballistic separation of the particles and these fractional oil cuts. In this first baffle is customarily associated a catalyst particle regenerator, on which coke is deposited within the cracking vessel. In this regenerator, the catalyst particles are regenerated by burning the coke and are then recycled towards the cracking baffle.
These types of installation are described in patent documents FR 2 625 509, FR 2 753 453 and FR 2 811 327.
Conventionally to achieve the combustion of coke in the regenerator by means of injected air at the base of the regenerator and the combustion gas containing in part carbon dioxide, resulting from the reaction of the oxygen in air and the carbon constituting the coke, is evacuated at the top part of the regenerator.
Carbon dioxide is a greenhouse-effect gas that should be reduced from emissions, bringing about a total or partial capture of this dioxide.
The carbon dioxide can be captured in a reactor by washing with a solvent, for example, monoethanolamine, which selectively solubilises the carbon dioxide. The solvent is then regenerated by extracting the carbon dioxide due to heating by injecting steam in another reactor then the regenerated solvent is returned to the scrubber unit. However, this solution has to be treated with nitrogen, which is also evacuated in part with the carbon dioxide at the top of the catalyst regenerator, which means proportioning the carbon dioxide trap in proportion with the quantity of nitrogen present. Furthermore, the thermal regeneration entails the inconvenience of requiring large quantities of steam. This solution therefore consumes a lot of energy.
Consequently, replacing the nitrogen diluent by recycled carbon dioxide and burning with an O2/CO2 oxidizer. However, the oxygen is produced from air by using an air separation unit with a cryogenic system that consumes a lot of energy.
Another process known to carry out gas combustion with integrated recuperation of carbon dioxide while using a metallic oxide used as an oxygen vehicle support. This oxide circulates between two reactors in which it is oxidized in a fluidized bed reactor circulating by mixing with air, is reduced by mixing with the gaseous fuel. This process has an advantage of not requiring an air separation unit since the oxide forms the oxygen support.
These carbon dioxide capturing processes have the inconvenience of increasing the investment cost twofold and they require large areas.
Therefore it has been considered as described in the patent document FR 2 850 156 to make a carbonaceous solid combustion facility to include a reactor for reducing oxides, a first cyclone, an exchanger for flue gas heat recovery, a reactor for oxidizing oxides, a second cyclone, exchangers for controlling temperature of the circulating oxides, in which circulates an oxide which is reduced and then oxidized in each of both reactors. According to this prior art, the solid combustible material is milled before entering the oxide reduction reactor. The oxides are reduced by first of all having them in contact with the fuel which reacts with the oxygen released by the oxide and then oxidized by contact with air which regenerates the oxide. The reduced size of the solid fuel particles allows more complete and faster combustion and production of nearly 100% of fly ash.
This type of facility for combustion of carbonaceous solid materials operating at atmospheric pressure with integrated capture of carbon dioxide does not require any prior air separation. Because of the simplicity and the compactness of this system the costs of capturing carbon dioxide may be reduced while providing production of steam for generating electricity.
The invention proposes an integration of a system of this type to capture the carbon dioxide emitted in a hydrocarbon conversion facility such as specified above. By using the invention, the carbon dioxide is captured, while providing the production of steam intended for the production of energy, and an optimal size and cost.